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GordonRamsey
09-23-2010, 10:20 PM
So I just got done watching the recent episode of mythbusters in where they tested to see if a car traveling at 100 mph crashing into a wall would be the same force as two cars traveling at 50 mph. It turns out that although the speed is doubled, the mass has ben as well, resulting the energy being distributed both the same as a single car crash at 50, and also a two car crash at 50. The 100 mph crash recorded an average (between the two sides) of 185 g's. The 50 mph (both single and head on) recorded around 53. Just something I found interesting.

Off hand, what is the g force that a human dies from?


And incase anyone was wondering this today, in order to knock someones socks off (literally), you will need to generate 30,000,000 newtons of force. Or a flatbed traveling at 65 mph with a 2x8 strapped to it.

Discuss?

Austin@STM
09-23-2010, 11:05 PM
If by knock there socks off you mean head :p

That is very interesting though, i never would have thought that was true.

GordonRamsey
09-23-2010, 11:11 PM
hahaha, that is true.

I recall a time in elementary school where they said the reverse was true. I've been lied to all these years. Stupid insufficient data!:mad:

vroom4
09-23-2010, 11:23 PM
These type of simple physics problems are ALL you do in beginning engineering classes.

If you jump off a boat that is traveling so and so onto a stationary boat, what is the resulting speeds and what not. Stupid inertia, energy, force balances, you never get away from them.

NickS VR4
09-24-2010, 09:57 AM
With the car thing, since the distance traveled to decelerate would be the same (distance of front of car to how ever far in the crushing goes) in the head on vs the wall, the amount of speed makes all the difference in the G force. Because 100 mph decelerating in 3ft, is much higher in force than 50mph decelerating in 3 ft. Now if the other car was a tank or bus travelling at 50mph and was much larger in mass than the other car, than it would come close to the 100mph impact.

When I first saw the results, i was shocked, but then I thought about it.